material recommendation for applying epoxy to very thin gaps and cracks

Does anyone have a material recommendation for applying epoxy to gaps and cracks?

I am making these silly fancy pencil holders, joining them along the grain w/ rip-cut miters, alla Wood Whisperer’s fancy pencil holder, except different. Anyhow, the table saws I TRIED using had some problems with their inserts and the tricky cuts came out a bit less than perfect. After gluing them I realized there was a reason I had initially ripped them at the size I did before—to make sure I still had wood to cut to get those miters perfect. Oh, well, since I don’t do this work at MY shop, time was limited and I forgot about that fact, deciding to join them anyway. Well, there ARE gaps, because the VERY SMALL change in level from the table surface to the insert surface changed a bit of the angle and… you get the point.

Now I will try to apply epoxy before in the time before I am allowed to use the power tools, and leave drying up while cutting other parts. So, I was wondering:

YOU GUYS HELPED ME WITH SOME EPOXY FIX A FEW MONTHS AGO. WHAT DO YOU USE TO APPLY/PUSH EPOXY INTO VERY SMALL, LONG GAPS? VERY THIN WIRE? WHAT KIND OF WIRE IS GOOD FOR THIS, DOES IT HAVE A NAME?

I do plan to contain the epoxy w/ tape (in fact, I might get frog tape to try and keep it from the surfaces to be finished.

I have another question re. epoxy. I know that people who work with Juniper use epoxy and sawdust from said piece to hide drill holes but, I have tried this and when I am trying to match the color of the epoxy mix with surrounding wood ( I use sawdust from same piece) I still can’t match the color, especially with the creamy colors…it turns sort of a dirty light brown. I have played with the ratio of sawdust to epoxy but, it doesn’t seem to matter.WHAT AM I DOING WRONG??

Nomad: that’s what I had done before, but this time the gaps are very thin/long, on a mitered corner joint and I don’t think the same procedure will work. Plus, when I tired that I kinda spread it around—some of it came of w/ sanding, a little bit of it became engrained and affected the finishing process. My finishing on that project was so horrible that it didn’t matter anyway.

I can’t take pictures because the cases are at the shop, which I visit only every Tuesday morning. I might want to take care of this before I go on w. the rest of the building process, or maybe not.

Mine will not look as pretty as those, but the “box” is the same construction, except w/ tiger maple scraps I got from a cabinet-door production shop (w/ a 1/3 to almost 1/2 of each face brown heartwood). The wood is gorgeous but I’m a tool and a noob, so they aren’t exactly marvelous. Anyhow, the gaps are on the corners.

The other thing is… it’s maple and epoxy will dry dark (as far as I remember), correct? Because CA is thinner, should I use that instead? Is there a CA brand you recommend?

Procedure I was think of:

Covering the outside of each corner to be treated w/ tape (frog tape?), to hold the glue in a “clean” form. Applying the glue from the inside and top of the gaps, sprinkling sawdust afterward. Let dry, take out tape, sand. Does that make any sense?